Sand conditioning apparatus



Aug. 11, 1959 s. M. BUTZOW SAND CONDITIONING APPARATUS 4 Sheets-Sheet 1 Filed March 14, 1957 INVENTOR. GEORGE M. BUTZOW y ATTORNEY Aug. 11, 1959 G. M. BUTZOW 2,898,651

SAND CONDITIONING APPARATUS Filed March 14, 1957 4 Sheets-Sheet 2 INVENTOR. GEORGE M. BUTZOW A T TORNE Y 1, 1959 G. M. BUTZOW 2,898,651

SAND CONDITIONING APPARATUS INVENTOR. GEORGE M. BUTZOW ATTORNEY Aug. 11, 1959 I G. M. BUTZOW 2,898,651

SAND CONDITIONING APPARATUS Filed March 14, 1957 4 Sheets-Shea 4 :02 -21.1 Ji l I:::

:41 PI .ll

INVENTOR.

GEORGE M. BUTZOW ATTORNEY United States Patent SAND CONDITIONING APPARATUS George M. Butzow, Fort Wayne, Ind.

Application March 14, 1957, Serial No. 646,060

6 Claims. (Cl. 22--89) The present invention relates to sand-conditioning apparatus and more particularly to apparatus having utility in foundries for conditioning sand used in making molds and the like for producing cast metal articles.

In the art of fabricating cast metal products, sand is commonly used for making the molds. In the foundry where molds are made, used and then destroyed, the sand from which the molds are made is re-used; however, before such reuse it must be reconditioned by breaking up any lumps, aerating or fluifing the sand, and adding the proper amount of moisture and other additives for tempering the sand.

In many instances, it is desirable to condition the sand immediately following its use. However, in many of the prior are apparatuses, it was not possible to recondition the sand thoroughly. By use of this invention, it is possible to recondition the sand thoroughly in a single operation without the need of further processing, such as aeration or seasoning.

It is an object of this invention to provide a sandconditioning apparatus which fulfills the need of efliciently reconditioning sand in a relatively short period of time so that it might be immediately reused.

It is another object of this invention to provide sandconditioning apparatus which is operative to mull, aerate and cool a batch of sand, all in a single operation and in a relatively short period of time.

It is still another object of this invention to provide sand-conditioning apparatus to which a batch of sand to be reconditioned may be delivered from a floor level and the reconditioned sand discharged to the same wheelbarrow on the same floor level. This results in the saving of complex and relatively expensive elevating apparatus which has heretofore been required for delivering a batch of sand to the reconditioning apparatus.

Other objects will become apparent as the description proceeds.

To the accomplishment of the above and related objects, my invention may be embodied in the forms illustrated in the accompanying drawings, attention being tion of Fig. 1 partially broken away for clarity of illustration; I 1

Fig. 6 is a fragmentary illustration in part cross-section showing the recycling and discharge chute assembly;

Fig. 7 is a view similar to Fig. 6 but in side elevation;

"ice

Fig. 8 is a perspective illustration of the pawl and ratchet mechanism used in positioning the flufiing wheel of Figs. 1, 2 and 4;

Fig. 9 is an end view of the apparatus of Fig. 1 partially broken away for clarity of illustration;

Fig. 10 is a sectional illustration taken substantially along section line 10-10 of Fig. 9; and

Fig. 11 is a partial view of the rocker arm mounting.

Referring to the drawings, and more particularly to Figs. 1, 2, 3 and 4, a transporting chassis or stationary frame 10 is composed of a base 12, upright members 14 and a horizontal platform 16 which comprises two longitudinally extending angle irons 1S and 20 (Fig. 8), these angle irons 18 and 20 being welded or otherwise rigidly secured to the upper ends of the uprights 14.

The chassis 10 is mounted on suitable wheels or casters 22 and 24 whereby the entire apparatus may be moved about over a floor surface as desired.

As will be noted in Figs. 1 and 2, the angle iron 18 extends for the full length of the apparatus, whereas the member 20 terminates near the center of the machine at 26. Horizontally spaced from and extending parallel to the platform member 18 is a similar frame member or angle iron 28 (Fig. 3), two bearings 30 and 32, respectively, being mounted on these two frame members 18 and 28.

Journalled in the bearings is an axle 34. Fixedly mounted on the axle 34 for rotation therewith is a mull ring or annular conveyor 36 which is composed of a discshaped supporting plate 38 having welded or otherwise secured'near the periphery thereof a cylindrically shaped rim 40. Secured on the rim 40 is an annular flange 42, and as will be noted in Fig. 4 both the supporting discs 38 as well as the annular flange 42 extend radially outwardly beyond the rim 40 for a purpose which will become apparent from the following. This mull ring 36 is preferably made of heavy gauge steel so as to be self-supporting on the axle 34 (Fig. 4). By this means, the mull ring 36 is rotatable between the frame members 18 and 28 on the axle 34.

Considering only Fig. l for the moment, an enclosure or housing, generally indicated by the reference numeral 44 encloses approximately the entire left-hand portion of the mull ring 36, this closure being rigidly mounted on the framework 10 and composed of heavy gauge sheet steel. Mounted in the front of this enclosure 44 (the front being that portion of the apparatus viewed in Figs. 1 and 7) is a discharge chute assembly as indicated generally by the reference numeral 46. This assembly 46 is supported between two spaced upright frame members 48 and 50, respectively, these members being secured at their lower ends to the longitudinally extending frame member 18 and at the top to a horizontally extending frame member 52 which is secured to and provides support for the front portion of the enclosure 44.

An inclined section 54 of the chute assembly having two upwardly extending sides 56 and 58 (Fig. 7) is fixedly secured between the two uprights 48 and 50, as shown. A hinge 60 is secured along the upper edge of this chute section 62, this section 62 comprising a fiat base 64 and a forwardly or outwardly extending arcuate side 66. A second hinge 68, mounted on the horizontal edge of the chute section 54, carries a lower chute section 70, this lower section 70 and the upper section 66 being connected together as by a suitable cord or chain 72.

As will be noted in Fig. 6, the upper and lower chute sections 66 and 70 may be lowered or otherwise swung about the respective hinges 60 and 68 by merely swinging the upper section 66 outwardly or forwardly to the dashed line position 74, the lower section 70 thereby gravitating to its dashed line position 76. Both sections 62 and 70 may be lifted or swung .to the full line positions by merely swinging the upper section 62 about its hinge 60, the lower section 70 being swung about its hinge 68 by means of the lifting cord 72. It may be noted at this point that when the apparatus is operating to recondition the sand, the two chute sections 62 and 70 are swung to the dashed line positions 74 and 76, respectively.

Disposed behind the chute assembly 46 just described is a deflecting plate 78 which in Fig. 7 is shown in dashed lines as inclined downwardly toward the left. This defleeting plate is rigidly mounted with respect to the framework 10 and preferably mounts on a short length of angle iron 80 which extends horizontally inwardly of the machine from a secure mounting on the frame upright 50. As will also be seen in Fig. 7, the lower end of the deflecting plate '78 terminates just inside the mull ring flange 42.

Suitably rigidly mounted on the frame upright 48 is a plow or deflecting plate 82 which in Fig. 7 is shown as being inclined upwardly and toward the right. This plow 82 terminates just short of the inner surface of the rim 40 for a purpose which will become apparent from the following description.

Disposed inside the mull ring and substantially di rectly beneath the chute assembly 46 is a mulling wheel 84 of conventional design. Preferably, this mulling wheel is provided with a rubber tire for reasons which are now well understood in the art. The wheel is rotatably mounted on an axle 86 supported by a rocker arm 88 which in turn is pivotally mounted on the longitudinal frame member 12 by means of a rock shaft 90. The

upper end 92 of the rocker arm 88 is spring urged in a counterclockwise direction by means of a suitable compression spring 94 which fits over two cylindrical spring seats 96 and 98, the spring seat 96 consisting of a reduced diameter strut which is pivotally mounted at 100 on the frame member 20 and the spring seat 98 being a similar reduced diameter strut which is pivotally mounted by means of the pin 102 on the upper end 92 of the rocker arm. As seen in Fig. 5, with the mulling wheel 84 so mounted it will roll on the rim 40 of the mull ring as the latter is rotated.

An adjusting bolt 97 is loosely received through an axially extending opening in the seat 96 to be threadedly received in an axially extending opening in the seat 98, rotation, of this bolt thereby serving to vary the spacing between the two seats 96 and 98. By drawing the two seats closer together, the spring 94 is compressed or loaded for correspondingly increasing the force which the mull wheel 84 exerts on the sand 166. Increasing the distance between these two seats conversely reduces the force thus exerted by the mulling wheel. The mounting of the seat 96 on the frame member 20 is made adjustable along the length thereof for providing a clearance adjustment between the mulling wheel and the'mulling ring. By proper correlation between the spacing between the seats 96 and 98, and the mounting of the seat 96 on the frame 20 (Fig. the proper mulling wheel pressure and clearance between the mulling wheel and the mull ring may be achieved.

On the front of the apparatus and slightly toward the right-hand side of the mulling wheel 84 (see Fig. 1) is a loading hopper 104 which extends outwardly away from the mull ring 36. The hopper is open at both the top and bottom, with the forwardmost panel as seen in Fig. 1 being inclined downwardly and inwardly to terminate just inside the mull ring flange 42. As noted, this hopper 104 is positioned about wheelbarrow-level above the floor whereby a wheelbarrow may be conveniently dumped into the hopper which guides the sand into the bottom portion of the mull ring 36.

Swingably mounted on the right-hand end of the frame members 12 as viewed in Fig. l are two spaced-apart uprights 108 (see Figs. 9 and These two uprights 108 are secured at the lower extremities thereof to a 4 horizontal pivot shaft 110 which is journalled at its opposite ends in two bearings 112, respectively, which are suitably secured to the underside of the frame members 12. To the upper ends of the two uprights 108 are secured two rods 114 which pass through two companion openings, respectively, in the cross-member 116 of the frame 10. On the two rods 114 are two compression springs 118, respectively, which bear against the member 116 and the respective nuts 120 on the threaded outer ends thereof. Thus, the uprights 108 are spring urged constantly in a clockwise direction about the pivot shaft 110.

Now referring more particularly to Fig. 10, it will be noted that the two uprights 108 carry two spaced bearings 122 which receive a horizontally extending jack shaft 124.. This jack shaft 124 is additionally journalled in two spaced bearings 126 to which are secured a carriage or platform comprising two horizontally extending angle irons 128. A cross-member '130 is secured to the right-hand ends (as viewed in Fig. 1) of these two angle irons 128 for mounting an electric motor 132 as shown more clearly in Fig. 9. Since the carriage 128 is freely swingable about the jack shaft 124, it must be supported in some manner, this support being provided by a flexible cable or chain 134 which is connected between the left-hand end of the carriage 128 (as viewed in Fig. 1) and to a ratchet shaft 136. This ratchet shaft is journalled in two suitable bearings 138 on the frame members 18 and 20 (see Fig. 8) and carries a handle 140 on its outer end and a ratchet wheel 142 in between. the two bearings. A pawl 144, engageable with the ratchet 142, is pivotally'mounted on a frame plate 146. as shown, in Fig. 8. By means of this ratchet mechanism, the carriage 128 may be positioned as desired, counterclockwise rotation of the handle 140 (as viewed in Fig. 1) serving to lift the left-hand end of the carriage 128.

On the left-hand end of the carriage. 128 are suitable bearings which receive a shaft 148. On the inner end of this shaft 148 is mounted a flufling or aerating wheel 150 (Fig. 4) which may be fabricated of a plurality of discs of reticulated metallic plates sandwiched together or of a multiplicity of metallic wires or bristles extending radially outwardly from a suitable hub. Other types of wheel construction will occur to the person skilled in. the art without departing from the scope of this invention.

It may now be noted that the proximity-of this fluffing wheel 150 periphery with the rim 40 may be adjusted by manipulation of the ratchet handle 140. The purpose of this wheel 150 will become apparent from the following description.

On the right-hand end of'shaft 136 (Fig. 8) is an arm 137 to which is connected a cable or rod 139.. The other end of the rod 139 is connected to an arm 141 which is secured to the rocker arm 92. Thus, clockwise rotation of lever 1.40 raises themulling wheel out of operative position.

On one end of the jack shaft 124 is a multiple grooved pulley 152, this pulley being drivably connected to the flufling wheel shaft 148 by means of suitable belts 154 and a pulley 156 onthe shaft 148. Also on the shaft 148 is another, pulley 158 which has a driving connection with the motor 132 by means of belts 160.

Also on the jack shaft 124 is a small diameter, multiplegrooved pulley 162 about which a plurality of v type belts 164 pass. As will be seen in Figs. 1, 2, 3- and 9, these belts 162 pass around the outer surface of the mull ring 36, whereby the latter may be rotated on its axle 34.

In operation, the chute assembly 46 is lowered to the dashed line positions 74 and 76 of Fig. 6. The motor 132 is energized, thereby causing counterclockwise rotation of the fluffing wheel 150, the jack shaft 124 and, the mull ring 36. The mulling wheel 84 is spring-biased against the rim 40 and correspondingly rotates. The fluifing wheel 150 is lowered to a position at which it just-clears the 40. After experience has been gained in -.the' operation of the machine, the precise operating position 'of this fluffing wheel 150 may be more accurately determined.

By selecting proper pulley sizes, the flufling or aerating wheel 150 is caused to rotate at a peripheral velocity of about three times that of the mull ring 36, or enough to accomplish desired action.

Sand to be reconditioned is dumped into the hopper 104 from which it gravitates into the bottom of the mull ring. The mull ring carries the sand with it in a counterclockwise direction, the sand first encountering the fiufiing wheel 150 which fluffs or aerates the sand and throws it outwardly and against the rim 40 of the mull ring. The mull ring continues to carry the sand around until it is intercepted by the plow 82 (Fig. 7) and deflected downwardly against the deflecting plate 78 from which it is discharged in front of the mulling wheel 84 (or the left-hand side of the mulling wheel 84 as viewed in Fig. 1). The sand thereupon passes beneath and is compressed by the mulling wheel 84 as indicated by the reference numeral 166 in Fig. 5

The machine is allowed to thus operate, the sand being fluifed and mulled as just described. The sand also undergoes a thorough mixing action by reason of the fact that the plow 82 and the deflecting plate 78 divert the sand against the backing plate 38 of the mull ring 36. By reason of this sand diversion, it constantly undergoes a rolling or swirling action which contributes to thorough mixing.

During this period of operation, a quantity of water may be added to the sand being treated as well as any of the other usual additives such as clay, cereals, sea coal, pitch, core oils and the like.

The mulling Wheel Serves to break up the baked and dry lumps in the sand which is initially dumped into the chute 104. Additionally, it squeezes the additives into intimate contact with the sand grains, thus coating the grains with'the materials which will cause the sand grains to adhere to each other when molded. However, as soon as the sand grains are thus coated with the additives, the muller wheel itself causes lumps and cakes to form by pressing the newly prepared sand (which is now moldable) against the mull ring. This necessitates, after mulling, the breaking down of these cakes and lumps but still preserving the moldability of the sand. Therefore, the lever 140 is swung clockwise far enough to withdraw the mulling Wheel 84 from the sand, the fluffing wheel 150 thereby breaking up these cakes and lumps, leaving "a powdery or fluify consistency of the necessary character for making high -grade castings. The period of time required for accomplishing this last flufling operation is very short and is done just prior to discharging the sand fromthe mull ring, as explained in the following.

After the sand has been circulated a suitable number of times, the operator merely swings the upper chute section 62 (Fig. 6) to its full line position, whereupon the sand deflected by the plow 82 (Fig. 7) is directed downwardly and outwardly from the chute 70. This discharge from the chute 70 may be received by a wheelbarrow placed therebeneath.

As-is well known in the art of making sand molds, it is highly desirable that the conditioned sand be flufly. Proper flufliness or aeration insures that the sand will flow freely and completely into all corners and crevices of the mold pattern, and by reason of being properly mulled, the sand will stick or adhere in place. Proper uniformity of sand density in the mold is thereby assured.

Shake-out sand, which remains after the casting has been removed, is sometimes lumpy as the result of ramming and heat reaction on the various additives. These lumps must be broken up into individual grains of sand to release the heat and be recoated with additives in the sandconditioning operation. The mulling wheel serves the function of breaking up-the larger lumps, while the flufling wheel 150 completes this function by pulverizing the lumps into individual grains. They both contribute to the process of recoating the sand grains with additives. Shake-out sand which has just been used is hot. In order to properly condition this sand, it is necessary that it be cooled and in prior art devices this cooling has been elfected by various means such as by air circulators. In this invention, however, the flutfing wheel constantly fluifs the sand and the plow 82. causes itto fall through the air from point of the plow to the muller wheel whereby the sand is cooled. By reason of this cooling action, hot sand from a used mold may be dumped into the machine, reconditioned and readied for reuse in a matter of only a very short period of time. The reconditioned sand is of proper temperature, consistency and composition, thereby conducing to efiiciency of foundry work.

Viewing Fig. 1, by positioning the plow 82 in the upper left-hand quadrant and the mulling wheel 84 in the lower left-hand quadrant of the mull ring, it will be noted that the sand deflects from the plow and drops on the mull ring in front of the wheel 84. The sand thus falls through space during 'which it is subjected to the cooling action of the surrounding air. Since very little power is consumed in so deflecting the sand from the mull ring, it is apparent that sand cooling is efliciently achieved. This being true, the power required of the motor 132 is a minimum, thereby leading to economy in the cost of the motor 132 as well as in the operation.

Economy of operation is primarily attributable to the fact that once a charge of sand is dumped into the chute 104 and is accelerated to mull rirrg speed, such speed is continuously maintained until the moment of discharge. In certain prior mulling machines in which a horizontal mulling bowl is used, the sand is continuously being plowed from a position of rest to a position just ahead of the mulling wheels, the sand thereby constantly undergoing rapid acceleration from a position of rest. The friction from this plowing action produces considerableheat which requires the use of auxiliary cooling apparatus thereby adding to the cost of the overall machine as well as to the cost of the operation. Since in the machine of this invention the sand undergoes only one instance of acceleration from rest and a cooling action takes place during sand gravitation between the plow 82 and the mull wheel 84, it is apparent that only a minimum of power is consumed in first operating the machine and secondly in efficiently cooling the sand.

In some instances, it is desirable to use an inner liner for the mull rim 40, this liner being made of a suitable rubber material. This improves the adherence of the sand to the mull ring and also extends its life, but experience has proven that this rubber liner need not necessarily be used.

What is claimed is:

1. Apparatus of the character described. comprising a supporting frame, an upright annular conveyor substantially open on one side and rotatably mounted on an axle carried by said frame for rotation in a given direction, a mulling wheel swingably mounted on said frame and being engageable with said conveyor, a fiufling wheel swingably mounted on said frame and disposed inside said conveyor, a plow type deflector mounted on said frame and disposed within said conveyor adjacent the top thereof, a chute hingedly mounted on said frame adjacent said deflector for delivering selectively sand from said conveyor, and a loading hopper on said frame adjacent the bottom of said conveyor.

2. Apparatus of the character described comprising a supporting frame, an upright annular conveyor rotatably mounted on a horizontal axle carried by said frame for rotation in a given direction, a mounting carried by said frame, a mulling wheel mounted for rotation on said mounting, a force-exerting device operatively connected to said mulling wheel for forcing the latter into engagement with said conveyor, a carriage pivotally mounted onsaid frame, a-flufling wheel mounted for rotation on said carriage about an axis substantially parallel to said axle and being disposed inside said conveyor, adjusting mechanism operatively mounted on said frame and having a connection with said carriage for adjustably positioning said flufling-wheel with respect to said conveyor.

3. Apparatus of the character described comprising a frame, a horizontally extending axle on said frame, an annular conveyor mounted on said axle for rotation in a given direction, said conveyor having a cylindrical periphery and being closed on one side and open on the other, a flange on the periphery extending radially inwardly, a mulling wheel positioned inside said conveyor for rolling engagement with said conveyor periphery, an arm supporting said Wheel from said frame, a spring operatively connected to said arm for urging said wheel into contact with said conveyor periphery, a flufiing wheel positioned inside said conveyor and rotatable about a horizontal axis, driving mechanism for rotating said flufling wheel faster than said conveyor in said given direction, a deflecting plow mounted on said frame adjacent the upper portion of said conveyor periphery, and a chute on said frame extending from the vicinity of said plow to a point outside of said conveyor, said chute being hingedly mounted on said frame for movement into and out of the vicinity of said plow, and a hopper having upper and lower openings disposed adjacent the lower portion of said conveyor for loading sand into said conveyor.

4., Apparatus of the character described comprising a frame a horizontally extending axle on said frame, an annular conveyor mounted on said axle for rotation in a given direction, said conveyor having a cylindrical periphery and being closed on one side and open on the other, a flange on the periphery extending radially inwardly, a mulling wheel positioned inside said conveyor for rolling engagement with said conveyor periphery, an arm supporting said wheel from said frame, an operating mechanism operatively connected to said mulling wheel for moving the latter away from said conveyor periphery, a flufiiing wheel positioned inside said conveyor and rotatable about a horizontal axis, a carriage swingably mounted on said frame and mounting said fluffing Wheel for rotation about an axis substantially" parallel to said axle, a motor on said carriage, driving mechanism operatively connecting said motor to said fluffing wheel and to said conveyor for rotating said flufling Wheel faster than said conveyor in said given direction, a deflecting plow mounted on said frame adjacent the upperportion of said conveyor periphery, and

a chute on said frame extending from thevicinity of said plow to a point outside of said conveyor, said chute being hingedly mounted on said frame for movement into and out of the vicinity of said plow.

5. Sand-conditioning apparatus comprising a frame, a horizontally extending first axle on said frame, an up right annular conveyor mounted on said axlefor rotation in a given direction, said conveyor having a cylindrical periphery and being closed on one side and open on the other, a mulling wheel operatively positioned inside said conveyor for roll-ing engagement with said conveyor periphery, a flufling Wheel mounted on a second" axle substantially parallel to said first axle, said second axle being operatively carried by said frame, means for rotating said fluffing wheel faster than said conveyor tioned in the lower portion of said conveyor, a discharge chute hingedly mounted on said frame adjacent said periphery and behind said plow for receiving sand deflected by said plow, and a loading hopper on said frame having sand-receiving and discharging openings adjacent the lower portion of said conveyor, said discharge opening being positioned inside said conveyor periphery'for delivering sand thereto.

6. Apparatus of the character described comprising, asupporting frame, an upright annular conveyor rotatably mounted about a horizontal axis on said frame for rotation in a given direction, a mounting carried by said frame, a mulling Wheel mounted for rotation on said mounting, said mulling wheel engaging said conveyor, a carriage movably mounted on said frame, a flufling Wheel mounted for rotation on said carriage about an axis substantially parallel to said axle and being disposed inside said conveyor, adjusting mechanism operatively mounted on said frame and having a connection with said carriage for adjustably positioning said flufl'ing wheel with respect to said conveyor.

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